Process of treating molded articles.



UNITED STATES PATENT OFFICE.

WALTER M. NEWTON, OF WYOMING, DELAWARE.

PROCESS OF TREATING MOLDED ARTICLES.

No Drawing.

To all whom it my concern:

Be it known that I, WALTER M. NEWTON, citizen of the United States,residing at Wyoming, in the county of Kent'and State of Delaware, haveinvented certain new and useful Improvements in Processes of TreatingMolded Articles, of which the following is a specification.

This invention relates to a process for the treatment ofmolded articleswhich are separated from the molds while in a plastic condition.

One of the principal objects of the invention is to provide a process ormethod of treating the article immediately after its separation from themold so as to eliminate defects such as mold marks, cavities, andcracks, and when such articles are composed of fine and coarse material,to bring the coarse particles into relief, creating a surface of variedand pleasing appearance.

Other objects and advantages of the process, applying especially toarticles molded of cement with other material, are to effect a morecomplete crystallization of the cement, a greater density of the productand increased strength and durability together with uniformity ofappearance and coloring.

It has been customary heretofore in the production of molded concreteobjects by the semi-dry process, to effect the most completecrystallization and fullest density by steam curing and the improvementin surface appearance by treating with chemicals, by scrubbing withsteel 'brushbs or by sand blast treatment, which methods can be employedonly when the cement is partially or fully set, and are slow, expensiveand unsatisfactory.

My invention has among its principal purposes the substitution of aquick reliable and etficient method for the tedious and expensiveoperation referred to, and one whichwill result in an improved productwithout To obtain the desirable results of my improved method ofprocedure, in carrying out my invention, I separate the-article from themold and apply to its surface a spray or mist which is projected againstthe article with whatever force is necessary to secure the resultsdesired, and at such angle to the surface of the article as its contourand the improvement desired may require. The

Specification of Letters Patent. Patented Aug. 30, 1910. Applicationfiled June 2, 1909. Serial-No. 499,764.

' spray or mist may be projected from a water pipe or hose having asuitable nozzle so constructed as to render a satisfactory spray ormist, and the pipe or hose may communicate with any source of supplyhaving the required head or force to create the necessary mist,'spray orvapor.

In molding concrete products from cement with sand gravel and stone agregates, by the semi-dry process, frequent y surface defects occur,such as cracks, rough edges and cavities, and when this is treated immediately before any crystallization of the cement,'with a spray ofproper density and force projected from a suitable angle, the cement on:the surface is taken up in solution by the water applied and flows intothe cracks and depressions where it blends with and becomes an integralpart of the completed article by crystallization assisted by themoisture of the spray.

In the semi-dry'manufacture of concrete products Without my process anaction of the cement which is termed the initial set is lost from lackofmoisture when first molded. With my process it is assured.

By the method herein described the parti'cles of sand and cement are notremoved or washed away from the face of the block or article, but arecarried from the more prominent projections into the cavities and,cracks, the force of the spray and the slight moisture only beingsufficient to bring out the coarse particles in relief upon the face ofthe article.

I claim:

The herein described method of treating molded articles made up of sand,cement, gravel and broken stones by the semi-dry process, which consistsin removing the article from the mold while in a semi-dry condition,projecting againstthe surface of the article an aqueous spray or vaporwith such force and at the required angle to the surface of the articleto eliminate defects in said surface by forcing the finer particles ofthe aggregates into the depressions, cavities or cracks by the force ofthe spray, thus bringing into relief the coarser aggregates, and thendrying the article.

WALTER M. NEWTON. Witnesses:

WILLIAM M. HOPE, JOHN B. VVHAn'roN.

